// jPaginate Plugin for jQuery - Version 0.3
// by Angel Grablev for Enavu Web Development network (enavu.com)
// Dual license under MIT and GPL :) enjoy
/*

To use simply call .paginate() on the element you wish like so:
$("#content").jPaginate(); 

you can specify the following options:
items = number of items to have per page on pagination
next = the text you want to have inside the text button
previous = the text you want in the previous button
active = the class you want the active paginaiton link to have
pagination_class = the class of the pagination element that is being generated for you to style
minimize = minimizing will limit the overall number of elements in the pagination links
nav_items = when minimize is set to true you can specify how many items to show
cookies = if you want to use cookies to remember which page the user is on, true by default
position = specify the position of the pagination, possible options: "before", "after", or "both"
equal = implements an equal height main element by using the highest possible element use true false
offset = unfortunately calculating heights with javascript isn't always 100% accurate, so please use this value to make it perfect :) its defaultly set to 50

*/
(function($){
    $.fn.jPaginate = function(options) {
        var defaults = {
            items: 2,
            next: "Next",
            previous: "Prev",
            active: "active",
            pagination_class: "pagination",
            minimize: false,
            nav_items: 6,
            cookies: true,
            position: "after",
            equal: false,
            offset: 50,
            elementtag: "tr"
        };
        var options = $.extend(defaults, options);

        return this.each(function() {
            //alert(options.elementtag);
            // object is the selected pagination element list
            obj = $(this);
            // this is how you call the option passed in by plugin of items
            var show_per_page = options.items;
            //getting the amount of elements inside parent element
            //var number_of_items = obj.children().size();
            
            var number_of_items = obj.find(options.elementtag).length;
            //var number_of_items = obj.find('span').length;
            //alert(number_of_items);
            
            //calculate the number of pages we are going to have
            var number_of_pages = Math.ceil(number_of_items/show_per_page);
            
            //create the pages of the pagination
            var array_of_elements = [];
            var numP = 0;
            var nexP = show_per_page;
			
            var height = 0;
            var max_height = 0;
            //loop through all pages and assign elements into array
            for (i=1;i<=number_of_pages;i++)
            {    
                array_of_elements[i] = obj.find(options.elementtag).slice(numP, nexP);

                if (options.equal) {	
                    
                    //obj.children().slice(numP, nexP).each(function(){
                    obj.find(options.elementtag).slice(numP, nexP).each(function(){
                        height += $(this).outerHeight(); 
                    });
                    if (height > max_height) max_height = height;
                    height = 0;
                }
				
                numP += show_per_page;
                nexP += show_per_page;
            }
            if (options.equal) {	
                max_height += options.offset;
                obj.css({
                    "height":max_height
                });
            }
			
			
            // display first page and set first cookie
            if (options.cookies == true) {
                if (get_cookie("current")) {
                    showPage(get_cookie("current"));
                    createPagination(get_cookie("current"));
                } else {
                    set_cookie( "current", "1");
                    showPage(get_cookie("current"));
                    createPagination(get_cookie("current"));
                }
            } else {
                showPage(1);
                createPagination(1);
            }
            //show selected page
            function showPage(page) {
                //obj.children().find(options.elementtag).hide();
                obj.find(options.elementtag).hide();                
                array_of_elements[page].show();
            }
            
            // create the navigation for the pagination 
            function createPagination(curr) {
                var start, items = "", end, nav = "";
                start = "<ul class='"+options.pagination_class+"'>";
                var previous = "<li><a class='goto_previous' href='#'>"+options.previous+"</a></li>";
                var next = "<li><a class='goto_next' href='#'>"+options.next+"</a></li>";
                var previous_inactive = "<li><a class='inactive'>"+options.previous+"</a></li>";
                var next_inactive = "<li><a class='inactive'>"+options.next+"</a></li>";
                end = "</ul><br clear='all' />"
                var after = number_of_pages - options.after + 1;
                var pagi_range = paginationCalculator(curr);
                for (i=1;i<=number_of_pages;i++)
                {
                    if (options.minimize == true) {
                        var half = Math.ceil(number_of_pages/2)
                        if (i >= pagi_range.start && i <= pagi_range.end) {
                            if (i == curr) {
                                items += '<li><a class="'+options.active+'" title="'+i+'">'+i+'</a></li>';
                            } 
                            else {
                                items += '<li><a href="#" class="goto" title="'+i+'">'+i+'</a></li>';
                            }
                        } else if (curr <= half) {
                            if (i >= (number_of_pages - 2)) {
                                if (i == curr) {
                                    items += '<li><a class="'+options.active+'" title="'+i+'">'+i+'</a></li>';
                                } 
                                else {
                                    items += '<li><a href="#" class="goto" title="'+i+'">'+i+'</a></li>';
                                }
                            } 
                        } else if (curr >= half) {
                            if (i <= 2) {
                                if (i == curr) {
                                    items += '<li><a class="'+options.active+'" title="'+i+'">'+i+'</a></li>';
                                } 
                                else {
                                    items += '<li><a href="#" class="goto" title="'+i+'">'+i+'</a></li>';
                                }
                            }
                        }
                    } else {
                        if (i == curr) {
                            items += '<li><a class="'+options.active+'" title="'+i+'">'+i+'</a></li>';
                        } 
                        else {
                            items += '<li><a href="#" class="goto" title="'+i+'">'+i+'</a></li>';
                        }
                    }
                }
                if (curr != 1 && curr != number_of_pages) {
                    nav = start + previous + items + next + end;
                } else if (number_of_pages == 1) {
                    nav = start + previous_inactive + items + next_inactive + end;
                } else if (curr == number_of_pages){
                    nav = start + previous + items + next_inactive + end;
                } else if (curr == 1) {
                    nav = start + previous_inactive + items + next + end;
                }
                if (options.position == "before") {
                    obj.before(nav);
                } else if (options.position == "after") {
                    obj.after(nav);
                } else {
                    obj.after(nav);
                    obj.before(nav)
                }
                
            }
			
            /* code to handle cookies */
            /* code to handle cookies */
            function set_cookie(c_name,value)
            {
                var expiredays = 999;
                var exdate=new Date();
                exdate.setDate(exdate.getDate()+expiredays);
                document.cookie=c_name+"="+escape(value)+
                ((expiredays==null)?"":";expires="+exdate.toUTCString());
            }
            function get_cookie(c_name)
            {
                if(document.cookie.length>0)
                {
                    c_start=document.cookie.indexOf(c_name+"=");
                    if(c_start!=-1)

                    {
                        c_start=c_start+c_name.length+1;
                        c_end=document.cookie.indexOf(";",c_start);
                        if(c_end==-1)c_end=document.cookie.length;
                        return unescape(document.cookie.substring(c_start,c_end));
                    }
                }
                return"";
            }
            
            function paginationCalculator(curr)  {
                var half = Math.floor(options.nav_items/2);
                var upper_limit = number_of_pages - options.nav_items;
                var start = curr > half ? Math.max( Math.min(curr - half, upper_limit), 0 ) : 0;
                var end = curr > half?Math.min(curr + half + (options.nav_items % 2), number_of_pages):Math.min(options.nav_items, number_of_pages);
                return {
                    start:start, 
                    end:end
                };
            }
			
            // handle click on pagination 
            $(".goto").live("click", function(e){
                e.preventDefault();
                showPage($(this).attr("title"));
                set_cookie( "current", $(this).attr("title"));
                $(".pagination").remove();
                createPagination($(this).attr("title"));
            });
            $(".goto_next").live("click", function(e) {
                e.preventDefault();
                var act = "."+options.active;
                var newcurr = parseInt($(".pagination").find(".active").attr("title")) + 1;
                set_cookie( "current", newcurr);
                showPage(newcurr);
                $(".pagination").remove();
                createPagination(newcurr);
            });
            $(".goto_previous").live("click", function(e) {
                e.preventDefault();
                var act = "."+options.active;
                var newcurr = parseInt($(".pagination").find(".active").attr("title")) - 1;
                set_cookie( "current", newcurr);
                showPage(newcurr);
                $(".pagination").remove();
                createPagination(newcurr);
            });
        });
        
       
    };
})(jQuery);